Synopsis
The XSPEC grbjet model: Two-phase Comptonization model of soft thermal seed photons for GRB prompt emission
Syntax
xsgrbjet The xsgrbjet model is an additive model component.
Description
The model is described at [1] .
Example
>>> create_model_component("xsgrbjet", "mdl")
>>> print(mdl)Create a component of the xsgrbjet model and display its default parameters. The output is:
mdl Param Type Value Min Max Units ----- ---- ----- --- --- ----- mdl.thobs frozen 5 0 30 mdl.thjet frozen 10 2 20 mdl.gamma thawed 200 1 500 mdl.r12 frozen 1 0.1 100 mdl.p1 thawed 0 -2 1 mdl.p2 thawed 1.5 1.1 10 mdl.E0 thawed 1 0.1 1000 keV mdl.delta frozen 0.2 0.01 1.5 mdl.index_pl frozen 0.8 0 1.5 mdl.ecut frozen 20 0.1 1000 keV mdl.ktbb frozen 1 0.1 1000 keV mdl.model frozen 1 -3.40282e+38 3.40282e+38 mdl.redshift frozen 2 0.001 10 mdl.norm thawed 1 0 1e+24
ATTRIBUTES
The attributes for this object are:
| Attribute | Definition |
|---|---|
| thobs | The observing viewing angle in degrees. |
| thjet | The jet half-opening angle in degrees. |
| gamma | The jet gamma Lorentz factor. |
| r12 | The jet radius in 10^12 cm. |
| p1 | The low-energy index of the coming frame broken powerlaw spectrum. |
| p2 | The high-energy index of the coming frame broken powerlaw spectrum. |
| E0 | The break energy in keV. |
| delta | The smoothness of the transition between the two powerlaws. |
| index_pl | The energy index of the comoving-frame cutoff powerlaw spectrum. |
| ecut | The cut-off energy in keV. |
| ktbb | The comoving frame blackbody temperature in keV. |
| model | The comoving frame emissivity law: 1 is broken powerlaw, 2 is cutoff powerlaw, and 3 is blackbody. |
| redshift | The source redshift. |
| norm | The normalization of the model: see [1] for an explanation of the units. |
References
- [1] https://heasarc.gsfc.nasa.gov/xanadu/xspec/manual/XSmodelGrbjet.html
XSPEC version
CIAO 4.16 comes with support for version 12.13.1e of the XSPEC models. This can be checked with the following:
% python -c 'from sherpa.astro import xspec; print(xspec.get_xsversion())' 12.13.1e
Bugs
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.